ODP: 3rd Re: ODP: optical pots 2

[Paul van Nugteren]

> It is thermal - the strip has an electrical resistance and is coated with
a
> temperature-sensitive liquid crystal material.  The LC changes color as
it
> heats up.  The color progresses up the scale because the resistance
changes
> over length.
> 
> Only problem with using it as an indicator is that it consumes a huge
amount
> of power ( by design ) and it's response time is very very slow.
> 
> 
> 
> You want to test the battery under load anyway so this works out to be a
> very cheap and accurate solution.
> 


And other LC's with faster responds time?  The power consumption wouldn't
be a problem (for the synth) but the response time could be faster if eg
changing patches.


Thanks,

Paul van Nugteren
> 
> -----Original Message-----
> From: Paul van Nugteren [mailto:PMvanNugteren at gmx.net]
> Sent: Tuesday, May 18, 1999 3:58 AM
> To: Roman Sowa
> Cc: synth-diy at mailhost.bpa.nl; synth-diy at mailhost.bpa.nl
> Subject: Re: ODP: 3rd Re: ODP: optical pots 2
> 
> 
> > This would be so so very cool!
> > I don't know how they do it, but I suspect you can use the strip
> > only few times. Besides I have no idea how to get its formula.
> > Duracell won't give it away, I'm sure
> > 
> > How about motorized pot? Only to drive indicator, not to use it
> > as a knob. Or any other kind of motor :-)
> > 
> > Roman
> > 
> 
> 
> Guess what? It's a chemical reaction controlled by a current! So al we
> would have to do is to put a current or voltage to the strip which has
> approx
> the same level as the knob has. 
> 
> Any chemists on the list?
> 
> 
> Thanks,
> 
> Paul van Nugteren
> 
> > > -----Oryginalna wiadomo¶æ-----
> > > Od:	P.M. van Nugteren [SMTP:PMvanNugteren at gmx.net]
> > > Wys³ano:	14 maja 1999 20:42
> > > Do:	Roman Sowa
> > > Temat:	3rd Re: ODP: optical pots 2
> > > 
> > > >         [Roman Sowa]
> > > >         Once I had a dream about ring of LEDs, say, 40 around a >
> rotary
> > > >         encoder showing aproximate value of every parameter. I saw
> > > >         something similar in mixing consoles (Neve range)
> > > 
> > > Do you know those DURACELL batteries which have got an indication >
> strip?
> > > If you push your tumb and indicator of the strip adjacent to the >
> poles
> > > of the battery, a chemical reaction starts an colors the strip >
> yellow.
> > > Well, I thought of an chemical indication like that on the DURACELLs
> > > around the knobs to show their position(in software), even if they >
> work
> > > relativly. The strip must be very cheap, a simple redox reaction. It
> > > could be glued to the surface of the sytnhs case.
> > > The demands are that the chemicals should work for a long time, the
> > > reaction should be quick. 
> > > This could be such a great gimmick that there might be even a >
> commercial
> > > interest in it.
> > > 
> > > Later,
> > > 
> > > 
> > > Paul van Nugteren
> > 
> 


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